package edu.sctu.practice.class02.liuli.practice.staticDuty;

/**
 * Created by Administrator on 2015/10/15.
 */
public class Circle {
    static int num = 0;
    double radius;
    double area;

    public Circle(double radius) {
        this.radius = radius;
        num++;
    }

    public double area() {
        area = Constant.PI * radius * radius;
        num++;
        return area;
    }
}

